SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d3a7ccf291039139eea8893c38cb63767b7a7ba946873d2620b490fa81fcd06' 
  AND token = 'AXnR4/HJc0Aj3svIvuktR0nOEpN1t6pqeFTWbvfnOhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}